在IIC驱动中
IIC_Read和IIC_Write函数中
都有ret = WaitForSingleObject(gI2CEvent, I2C_RW_TIMEOUT);
其中I2C_RW_TIMEOUT定义为： #define I2C_RW_TIMEOUT 2000
具体函数：
DWORD IIC_Read(DWORD Handle, LPVOID pBuffer, DWORD dwNumBytes)
{
UINT32 count, ret;
uchar *pReadBuffer;
if ((pBuffer == NULL) || (dwNumBytes <= 0))
return 0;
pReadBuffer = MapPtrToProcess(pBuffer, GetCallerProcess());
// 设置从机地址及当前状态
I2cCurSla = I2cSla | 0x01;
I2cStatus = I2C_STATUS_SETADDR;
StartI2C(I2cCurSla);
ret = WaitForSingleObject(gI2CEvent, I2C_RW_TIMEOUT); /* 挂起当前线程,直到IIC中断的产生 */
ResetEvent(gI2CEvent);
if ((IICError != I2C_ERROR_NO_ERR) || (ret != WAIT_OBJECT_0))
{
RETAILMSG(1, (TEXT("ERROR: IIC_Read: Send Slave Address fail! \r\n")));
return 0;
}
I2cStatus = I2C_STATUS_RECEIVE; // 进入接收状态
for (count = 0; count < dwNumBytes; count++)
{
if (count == (dwNumBytes - 1))
IIC_StartRecByteNA();
else
IIC_StartRecByteA();
/* 挂起当前线程,直到IIC中断的产生 */
ret = WaitForSingleObject(gI2CEvent, I2C_RW_TIMEOUT); ResetEvent(gI2CEvent);
if (ret != WAIT_OBJECT_0)
{
if (ret == WAIT_TIMEOUT)
RETAILMSG(1, (TEXT("ERROR: IIC read data time out! \r\n")));
else
RETAILMSG(1, (TEXT("ERROR: IIC read data fail! \r\n")));
return count;
}
*pReadBuffer = IIC_RecByte();
pReadBuffer++;
if (IICError != I2C_ERROR_NO_ERR)
{
RETAILMSG(1, (TEXT("ERROR: IIC_Read: Receive data fail! \r\n")));
break;
}
}
StopI2C(0);
return count;
}
------解决方案--------------------
等待gI2CEvent事件的发生，如果2秒后事件没有发生，就超时处理
如果gI2CEvent事件发生了，就马上wait返回，ret == WAIT_OBJECT_0